Single partion for bootloader + rootfs

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1

@Robert C Nelson,

Hey Robert, I am wondering where I should look to find out how you create a 1MB “hole” in the beginning of the bootloader ( MLO / u-boot, etc ) for the new Debian images. I do have a vague understanding of what to do, to create, but no idea of how to reverse this process, for when I wish to create an NFS rootfs to test future testing images.

Could it be as simple as dd-ing the first Megabyte of the device ? In the past using your guide, it was really easy. Just put the bootloader files on a FAT partition, and then move the rootfs onto an NFS share - Instead of a second partition on the same sdcard. Now . . . not quite so easy.

2

Most partition utilities actually start with a 1MB offset (due to 4k
native drive), we just make sure to enforce it via sfdisk:

sudo sfdisk --in-order --Linux --unit M ${DISK} <<-__EOF__
1,0x83,*
__EOF__

If you were to to change the above 1 to a zero, it would still default
to some offset above zero to make msdos/mbr happy...

Regards,

3

Ok, so the typical dd + loop device “trick” should work ? I’ve never actually tried playing with the MBR of a device before . . . Now, it is starting to seem less “magical”. In the past, I had imagined that the MBR contained “raw code”, no file(s), etc. Now I feel a bit silly for not looking into this . . .